How to Turn a Pedal Schematic Into a BOM
Walk a guitar-pedal schematic and produce a clean Bill of Materials: how to group parts, note tolerance/voltage, and export a supplier-ready CSV from Pedal Bench.
What a BOM is and why you actually need one
A Bill of Materials is the shopping list version of your schematic. Every component you need to buy, the quantity, and ideally the supplier part number — collapsed into one tidy table. You take it to Mouser, Tayda, or Smallbear and it tells you exactly what to drop in the cart.
Without a BOM you'll order the wrong cap value, forget the trimpot, and then wait a week for a $4 part. With one, you walk in and walk out.
Walking the schematic by hand
If you're rolling your own BOM, do it methodically. Open the schematic and go in passes:
- Pass 1 — resistors. Roll up duplicates (three 10 kΩ = one line item, qty 3). Note tolerance if any of them are 1% precision.
- Pass 2 — capacitors. Note type (ceramic / film / electrolytic) and voltage rating. A 47 µF cap might be 16 V or 25 V; the wrong one won't fit your enclosure.
- Pass 3 — diodes and transistors. Be exact about part numbers; a 2N3904 and a 2N5089 are not interchangeable in a pedal.
- Pass 4 — pots, switches, jacks, knobs, enclosure, DC jack, LED, LED bezel.
- Pass 5 — the boring stuff people forget: hookup wire, IC sockets, PCB standoffs, rubber feet.
That last pass is the one that turns a finished pedal into a rattling pedal that scrapes your pedalboard.
What good BOM rows look like
Each row should have: reference designator (R1, C3), value, type/package, quantity, and a supplier part number. For passives, group by value — refs separated by commas, total qty at the end. Example:
- R1, R4, R8 — 10 kΩ — 1/4 W, 5% — qty 3 — Tayda A-1490
- C2, C5 — 100 nF — film, 63 V — qty 2 — Tayda A-2069
- IC1 — TL072 — DIP-8 — qty 1 — Mouser 595-TL072CP
That's enough information that anyone (including you, a year from now) can rebuild the pedal.
Let Pedal Bench do the boring part
Open any saved project, click Export BOM, and you'll get a CSV pre-filled with all of the above, plus suggested suppliers and live links to current part numbers. The Supplier tool can re-price the whole list against Mouser or Tayda in one click, which is genuinely useful when prices drift.
For pedals you found in the Library, the BOM is already built — open the project, hit Export BOM, done. You can then tweak it (swap a clipping diode, change an electrolytic to a film cap) and re-export.